Electric-railway conductor



(No Model.)

E. THOMSON.

ELECTRIC RAILWAY CONDUCTOR.

No. 446,483. P44411444 Feb. 17, 1891.

WIT/M58858. Ill/VENTOI? I By I ATTORNEY.

ELIHU THOMSON, OF LYNN, MASSACHUSETT ELECTRlC-RAILWAY CONDUCTOR.

SPECIFICATION forming part of Letters Patent No. 446,483, dated February 17, 1891. Application filed March 22, 1890. Serial No. 344,938. No model.)

To aZZ whom it may concern.-

Be it known that I, ELIHU THOMSON, a citizen of the United States, residing at Lynn, county of Essex,State of Massachusetts, have invented certain new and useful Improvements in Overhead Conductors for Electric Railways, of which the following is a specificat-ion.

My invention consists in an improved manner of supporting the bare trolleywire, in supplying the same with current, and in protecting it from short circuits or grounds caused by the falling upon it of other wires, such as telephone, telegraph, or signaling wires.

The invention also consists in an improved way of attaching the span-wires or cross supporting-wires to the overhead conductor, so as to obtain the greatest insulation or resistance between the trolley-wire and earth.

Briefly, the invention consists in suspending the bare trolley wire or conductor below an insulated feeding-conductor run parallel with it, the former being connected to the latter at properintervals for obtaining adequate mechanical support and points of attachment for supplying current sufficient in number to maintain an economical electro-motive force of the current, thus preventing undue losses in the overhead conductor by a falling off in the potential of the current supplied to the motors on the car.

It also consists in placing one or more feedin g-conductors thoroughly insulated th roughout their length immediately above the trolley-Wire proper and in attaching the span or cross supporting wires directly to such insulated conductor or conductors in suchfashion that in wet and rainy Weather long insulatin surfaces must be covered with moisture before current can leak to earth, while at the trolley-wheel is attached to and supported by the upper insulating and feeding conductor. Fig. 3 shows a modification in which two in sulated conductors are placed above the bare eient mechanical strength when attached to guy or cross wires XV \V, suitably secured thereto at intervals along the line and of sufficient conductivity to convey current to the motors 011 the cars without too great drop in the electro-motive force. This conductor 0 is heavily insulated with, for example, a good braided insulation, which insulation may be impregnated with pitch, rubber, or other moisture-resisting material, while the braiding itself is made hard and dense, so that it will resist great mechanical abrading action, while retaining its integrity as an insulator unimpaired. Thus if a bare wire 2/) should be broken and fall upon the conductor 0, and

through any agency, as by the Wind, be drawn backward and forward over it, producing a sawing action, the insulation of the conductor 0 would resist such sawing action and remain intact for a reasonable time.

E E E &e., are cars depending from the conductor 0 and secured to the trolley-wire T in any suitable manner, as by soldering or clampin These ears E E, 850., are attached at sufficiently frequent intervals along the line to provide ample mechanical support and feeding-points for current to the trolley-wire T, and may be situated, say, six to eight feet apart. The spairwires \V may be connected to the conductor C by suitable clamping devices, as at D, which may embrace such conductor O and thoroughly insulate it from the span-wire, the points of attachment to the conductor C being by preference about midwaybetween the depending ears E E, &c., so that a long insulating-surface exists between the bare metal at the clamps E E and the span-wire To afford still greater safety from leakage to earth or short circuits, additional insulation may be provided in the supporting devices D D.

In Fig. 2 is illustrated one of the ways in which the ears E E may be attached to the conductor 0 and the trolley-wire T. The conductor C may be bared of its insulation for a distance, the ear E, riveted or soldered in po sition or otherwise suitably secured thereto,

ICO

the attachment to the trolley-wire T being made in a similar manner. An insulatingtape may then be wound over the joint so made with the conductor O to restore the insulation at this point.

In Fig. 3 is illustrated a modification of the invention, in which two feeding, insulating, and supporting wires 0 C are used, which are connected to the trolley-wire T in the same way as seen in Fig. 2; but the ears must in this case also be covered with insulation between the conductors G O to prevent possible contact at this point with a fallen wire. The hooded support D is secured in like manner to both conductors C C, as shown. The ears E and the hooded supports D are in this case, however, made in such a way as.

to brace the conductors G C and hold them at the proper distance apart. This arrangement is even better, so far as a shield for falling wires is concerned, than the arrangement, Fig. 1; but it is more expensive to construct and less sightly. It might, however, be employed to advantage in many instancesas, for example, where there are very many overhead wiresbelonging to telephone, telegraph, and other. signaling systems.

What I claim as new, and desire to secure by Letters Patent, is-

l. The combination, in an electric railway, of a main conductor having an insulatingcovering and suspended above the roadway, and a bare contact-conductor placed beneath the said main conductor and carried by supports therefrom at points intermediate between the supports of the main conductor.

2. The combination, with a main supplyconductor for an electric railway, having an insulating-covering and suspended above the roadway by insulating-Snpports, of abare contact-conductor placed beneath the said main conductor and supported therefrom by means of conducting attachments placed at points intermediate between the supports of the said main conductor.

3. The combination, in an electric railway, of a series of transverse supporting-wires, a main insulated conductor suspended therefrom by insulating-supports, and a bare contact-conductor connected by means of attachments to the said main conductor at points intermediate between the supports of said main conductor.

4. The combination, invan electric railway, of two insulated supply-conductors suspended above the roadway, and a bare contact-conductor suspended in a symmetrical position below the two supply-conductors and supported therefrom.

5. The combination, in an electric railway, of two main: supply-conductors supported above the roadway, and a. bare contact-conductor suspended in a symmetrical position between the two main conductors and electrically connected by attachments thereto at points intermediate between the supports of the said main conductor.

ELIHU THOMSON.

\Vitnesses:

JOHN W. GIBBONEY, WMT. PLUMSTEAD. 

